Effect of Gd sub(2)O sub(3) addition on mechanical, thermal and shielding properties of Al sub(2)O sub(3) ceramics

• Published in: Journal of materials science. Materials in electronics 2017-04, Vol.28 (8), p.5898-5905
• Main Authors: Ge, Rong, Zhang, Yan, Liu, Yujian, Fang, Jun, Luan, Weilin, Wu, Guozhang
• Format: Article
• Language: English
• Subjects: Aluminum oxide; Bend strength; Ceramics; Forsterite; Gamma rays; Heat transfer; Radiation shielding; Thermal conductivity
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-016-6263-x

Gd sub(2)O sub(3)/Al sub(2)O sub(3) ceramic composites with different weight percent of Gd sub(2)O sub(3) were prepared by adopting a pressureless sintering approach. The effect of Gd sub(2)O sub(3) addition on the phase composition, sintering property, microstructure, bending strength, thermal conductivity and shielding property of the composites was investigated. The results show that the properties of ceramic can be improved greatly by introducing a small amount of Gd sub(2)O sub(3), owing to the promotion of reaction between MgO, SiO sub(2) and Al sub(2)O sub(3) to produce spinel and forsterite. Compared with ordinary Al sub(2)O sub(3) ceramic, the bending strength and thermal conductivity coefficient of Gd sub(2)O sub(3)/Al sub(2)O sub(3) composite with 5 wt% Gd sub(2)O sub(3) have increased by 38.03 MPa and 8.95 W/(m K), respectively. When the amount of Gd sub(2)O sub(3) surpasses 15 wt%, however, the performances of the composite would become worse for excessive new phases formed in the composite hindering its densification. In addition, screening ratio of the composites for Co-60 gamma rays radiation increases with the addition of Gd sub(2)O sub(3). And the Gd sub(2)O sub(3)/Al sub(2)O sub(3) composites also exhibit good mechanical stability when exposed to continuous gamma rays irradiation.